Abstract:
Particleboards were prepared from three wood species, namely Acacia nilotica ( sunt ) Boswellia papyrifera (gafal ) and Ailanthus excelsa, using three resin levels ( 9, 12 and 15 % ) and three pressing times ( 6, 8 and 10 minutes ). Prior to testing, the boards were conditioned for one week at a temperature of 25° C and relative humidity of 65%. The boards were evaluated by testing the following properties: modulus of rupture, modulus of elasticity, internal bond, water absorption and thickness swelling after two hours and twenty four hours soaking in water. Modulus of rupture (MOR) was highest for Sunt boards with 15% resin level, followed by ailanthus with no significant difference between them. It was lowest in case of Gafal boards and 9% resin level. Modulus of elasticity (MOE), on the other hand, was highest with Ailanthus boards and 15% resin level, and lowest with Gafal boards and 9% resin level. Internal bond (IB) was highest with Sunt boards followed by ailanthus without a significant difference between them and 15% resin level. Water absorption after 2 and 24 hours soaking in water (WA2 and WA24) and thickness swelling (TS2 and TS24) after 2 and 24 hours soaking, showed similar trends. The best boards were those made of Sunt and 15% resin levels, while the worse were those made of Ailanthus and 12% resin level.
